I'm not going to say yes to something when I'm not quite sure what the question is. I'll say yes, maybe, because I'm not quite sure what the question is.
There is one atmosphere and carbon is well mixed, yes, that's true. But I don't think the IPCC concluded anything about all countries having to work together. I truly believe that this issue, which is the single-biggest issue facing humanity, will unify all countries, because it has to. It will have to if it hasn't already, but I don't think we've prescribed that in the IPCC process.